Why this is a fundamental, not an afterthought
On a bolt gun, manipulations are slow and deliberate by design. On a carbine, the ability to reload smoothly and clear a malfunction quickly is part of marksmanship — a hit you can't follow up because the gun is empty or jammed is an incomplete skill. These manipulations should be trained to the point of being automatic, because they'll always happen at the least convenient moment, and fumbling them under stress is how people get hurt or lose a match stage.
Safety first, always: these are dry-practice skills before they're live. Practice with an unloaded rifle and dummy rounds until the motions are smooth, then layer in live fire.
The reload, two flavors
Speed (emergency) reload — the gun runs dry mid-string and you need it back now. The bolt has locked back on an empty magazine. The sequence: keep the rifle mounted and your eyes on the target, bring the rifle slightly inboard so you can see the magwell in your peripheral vision, hit the magazine release and let the empty mag fall to the ground (don't try to save it — speed matters more than the magazine), drive a fresh magazine in firmly and tug to confirm it's seated, then release the bolt (bolt release or charging handle) to chamber a round, and drive back onto the target. The empty mag is sacrificed for speed.
Retention (tactical) reload — there's a lull and you want to top off while keeping the partial magazine. Here you retain the partial mag (stow it) rather than dropping it, swapping in a full one during a pause in the action. Slower, deliberate, used when time allows and you don't want to lose rounds.
The key habits for both: keep your eyes on the threat/target as much as possible, confirm the magazine is seated with a tug (an unseated mag is a guaranteed stoppage on the next shot), and make the motions smooth and consistent rather than frantic — smooth is fast.
Immediate action: "tap, rack, reassess"
The great majority of carbine stoppages (failure to fire, failure to feed, a bad seat) are cleared by one reflexive drill, often called immediate action or "tap-rack":
Tap — firmly seat the magazine with the heel of the support hand (the most common cause is an unseated mag). Rack — vigorously run the charging handle to the rear and let it fly forward, ejecting whatever's in the chamber and feeding a fresh round. Reassess / re-engage — get back on the sights and, if the target still needs it, fire. Tap-rack-reassess clears most stoppages in about a second without diagnosis.
When tap-rack doesn't work
A small percentage of malfunctions are worse — most notably the double feed (two rounds trying to occupy the chamber at once) and a failure to extract. These won't clear with tap-rack and force it harder. The remedial action is longer: lock the bolt to the rear, strip the magazine out, rack the action several times to clear the obstruction, then reload and re-rack. It's slower and you'll feel the difference — tap-rack meets resistance and the gun stays dead. The skill is recognizing "this isn't clearing" quickly and switching to the remedial drill rather than mashing the charging handle uselessly. These are rarer; train them, but train tap-rack to true reflex first because it solves most problems.